Rep. Howard Berman has out-raised fellow Democratic Rep. Brad Sherman recently, but Sherman had more cash left to spend — about $4 million to Berman's nearly $2.5 million.

Two veteran congressmen fighting for their political lives have amassed millions as they battle for a single San Fernando Valley seat, dwarfing the war chests in most other hot House races in Southern California this year.

Rep. Howard Berman has out-raised fellow Democratic Rep. Brad Sherman recently, but Sherman had more cash left to spend — about $4 million to Berman's nearly $2.5 million — new campaign filings show. A "super PAC" that supports Berman's candidacy reported large contributions from two Los Angeles-area business titans, according to reports filed with the Federal Election Commission.

Sherman started the race for the newly drawn, strongly Democratic district well ahead of Berman, having stockpiled cash from earlier campaigns. A relatively small portion of Sherman's campaign treasury comes from loans, including an interest-free $250,000 from his personal funds last year. He also has raised $37,000 for the 2014 campaign, mostly from donors who have already given the maximum amounts allowed for the current race.

Berman campaign senior advisor Brandon Hall accused Sherman of "padding his fundraising numbers" through the 2014 donations, which can't be spent in the current race, and the loans. Sherman spokesman John Schwada called that assertion "silly," noting that the 2014 donations amount to less than 1% of Sherman's stockpile. The loans, Schwada said, should be viewed as a "counterbalance" to the donations of super PACs, which can independently receive and spend unlimited amounts to support or oppose candidates. At least two such groups have formed to support Berman, records show.

One, the Committee to Elect an Effective Valley Congressman, reported contributions of $100,000 each from shopping center magnate Peter S. Lowy and Mapleton Investments, a firm headed by venture capitalist Marc Nathanson. Throughout the campaign, Sherman has challenged Berman to spurn super PACs by signing a pledge to offset their spending with contributions to the U.S. Treasury from his own campaign. Berman, calling that proposal "a gimmick," has refused.

Berman took in $577,000 during the first three months of the year, the period covered by the latest filings. That is more than twice the $202,000 collected by Sherman at the same time. Berman's total fundraising for this election has reached nearly $3 million, while Sherman has added about $1,043,000 to his already considerable campaign fund since the two congressmen's homes were thrown into the 30th Congressional District during last year's redrawing of political maps.

But Berman has spent $1.7 million, while Sherman reported spending less than $1 million so far. Because of the state's new election system, which sends the top two finishers in the June primary to a runoff in November — regardless of their party affiliation — the Berman-Sherman clash is expected to last through the fall.

Although fundraising has been brisk in several other strongly contested Southern California races, no other congressional candidate matched the Valley pair's bank balances.

In another race pitting two Democratic Congress members against each other, Rep. Janice Hahn of San Pedro collected $209,800 to Rep. Laura Richardson's $81,075. Hahn reported having $174,664 on hand but had debts of $141,429; Richardson, of Long Beach, had $116,186 but debts of nearly $450,000.

In the crowded race for a Ventura County seat, state Sen. Tony Strickland (R-Moorpark) and Assemblywoman Julia Brownley (D-Santa Monica) led in fundraising. The filings showed Strickland raised nearly $771,000 and had $732,000 remaining, while Brownley collected $256,000 and had about $254,000 left.

In Santa Barbara County, Democrat Rep. Lois Capps reported raising $524,000 and had $1.3 million on hand. One of her two Republican challengers, former Lt. Gov. Abel Maldonado, raised about $194,240 and has more than $492,000 in the bank. The other, actor/writer/businessman Chris Mitchum, collected $18,600 and had nearly $114,000. He owes more than $110,000.